Streams¶

Streams can be found next to the App Dashboard in another Tab.

The Stream-resources Consumers, Producers and Connectors serve the purpose of defining data streams. There is a hierarchy to these resources in which Connectors form the foundation for Consumers and Producers. Hence, the definition of a data stream consists either of a Connector-Consumer pair or a Connector-Producer pair. Each Consumer and each Producer runs on exactly one connector. Connectors, on the other hand, can have many consumers and producers.

As the name suggests, Connectors take information on overall connection parameters, such as addresses and authentication details. Especially if several message streams are on a broker, server or other “data space”, Connectors contain information which can be shared by Consumers and Producers. Consequently, shared information has to be defined only once in one place.
Consumers are used to define the input message stream of Streamsheets. They are added to the Inbox of a Streamsheet
Producers are used to define outgoing message streams. They are referenced in stream functions like MQTT.PUBLISH().

In the following we will use MQTT as an example stream:

Connector¶

A Connector is always the foundation of our communication architecture. Consumer and Producer reference to a Connector and define the details. The connector itself “connects” the Streamsheet to a provider, you can choose from a preconfigured list. Once a provider is choosen, there are a variety of settings, which can be applied to define the details of your data stream.

MQTT Connector¶

The MQTT Connector has the following possible settings.

Name: The Name of your Connector
Provider: you can´t change the provider. You choose it while creating the connector.
URL: Choose the MQTT Broke you want to use. If you want to use our own broker, which is hosted by the Stream Sheet Server, type in broker
Port: Choose the port you will be using to transfer the data.
User Name & Password: If your URL needs identification, you can type in your credentials. For local usage not neccessary.
Base Topic: The Base topic describes where the connector will be connected to.
Retain Message:
QoS: Stands for quality of service. You have the choice between: At most once, At least once, Exactly once.
Protocol Versio: MQTT Broker can run on different protocols.

Producer¶

A Producer is used in a Function. It directs the data stream out of the Stream Sheet. The Function together with the Producer defines where your data will be heading. A Producer is always connected to a Connector, which serves as the foundation of a Producer. Once the Connector is choosen, there are some additional settings within the Producer.

MQTT Producer¶

The MQTT Producer has the following possible settings:

Name: The Name of your Producer.
Connector: Choose the connected Connector.
Data Format: Choose the Data Format a Producer will publish the Messages in.
Topic: Extend the Base Topic of the Connector. The Message will be sent to the full topic branch defined through Connector, Producer and Function (ConnectorTopic/ProducerTopic/FunctionTopic).
Clean: turn on clean session
Static Client ID: set a static client ID if needed

Consumer¶

A Consumer is always connected to the Inbox of a Stream Sheet. It defines the details of the data stream comming into a Stream Sheet. A Consumer is always connected to a Connector. Once the Connector is choosen, there are some additional settings within the Consumer.

MQTT Consumer¶

The MQTT Consumer has the following Settings:

Name: The Name of your Consumer.
Data Format: Choose the Data Format you wish to accept in the Inbox.
Static Client ID: set a static client ID if needed
Topics: Choose one or more topics the Consumer will listen to. The topics always extend the Connector Base Topic.
Clean: turn on clean session